Prince Andrew’s former friend Jeffrey Epstein used “aggressive witness tampering” on his employees who later refused to answer questions about the prince, US investigators have said.

Multi-millionaire Epstein is also alleged to have paid witnesses who invoked their right to silence when asked whether young girls were used for sex with the prince.

Prince Andrew, who has “categorically denied” the claims made in US court documents alleging that he abused a 17-year-old girl or engaged in “impropriety with under-age minors, spent much of yesterday in discussion with lawyers at his residence in the Royal Lodge in Windsor. He and his staff have refused to answer any further questions on the allegations.

The Telegraphreports that the documents filed in a Florida court reveal the great frustration felt by legal representatives of the alleged victims in their attempts to gather evident. Lawyers complained that it became “impossible” to gather evidence from witnesses because so many had their legal representation paid for by Epstein.

One statement lists ten of Epstein’s employees and associates who were being represented by lawyers paid for by Epstein, including Nadia Marcinkova, who has been described as his “live-in sex slave” but invoked her right silence under the US Constitution’s Fifth Amendment when asked about Prince Andrew.

When asked if she’d ever been made to “perform sexually on Prince Andrew”, she simply responded: “Fifth”. The court papers also allege that she was “harassed” by Epstein not to cooperate with investigators.

Another person listed is Sarah Kellen, who worked as Epstein’s executive assistant. When asked whether Epstein and Prince Andrew shared under-age girls for sexual relations, she replied: “On the instruction of my lawyer, I must invoke my Fifth Amendment privilege.” Kellen also had her legal representation paid for by Epstein, and it is alleged Epstein “threatened” her to prevent her from cooperating.

A former model, Adriana Ross, who worked as Epstein’s diary manager, also refused to answer when asked whether she had any knowledge of Prince Andrew being involved with under-age minors.

Epstein himself refused to answer questions on whether he provided under-age girls for the prince.

The claims that Prince Andrew sexually abused 17-year-old Virginia Roberts emerged during the latest attempt by alleged victims to overturn the Epstein’s plea deal. Miss Roberts and another complainant argue that the deal was unlawful because alleged victims were not consulted.